Objective:To develop the mechanistic model for the reorientation of T cell receptors during immunological synapse formation.Methods:Based on the theory of energy transfer during double-molecular reactions in the context of classical fluid mechanics,a vortex-driven model was proposed where in the coupled receptor/ligand molecules within the immunological synapse recruit the T cell receptors.Results:The model results indicated that driven by the consecutive vortexes with specific combinations of strengths and acting frequencies of vortexes,TCR transport speed can reach the values matching up to the experimental measurements(0.04-0.1 ?m/s).Conclusion:The model demonstrated that during the coupling,the membrane-tethered receptor-ligand pairs may transform their binding energies into the rotational energies of the reactants,thereby leading to the vortexes of the surrounding water continuum insider and outside the T cell,and these resulting vortexes may function as the engines for the reorientation of T cell receptors.

BACKGROUND: Some experiments indicated that applying rosiglitazone on diabetic animals lacking of insulin could not increase insulin and lower blood glucose obviously, which showed that rosiglitazone did not stimulate the excretion of rosiglitazone. The action of rosiglitazone in improving insulin resistance and the effects on the functions of liver and kidneys need more investigations.OBJECTIVE: To investigate whether rosiglitazone can improve the insulin resistance of rats with hyperlipemia, and analyze the possible mechanism.SETTINGS: Guangzhou Hospital of Traditional Chinese Medicine; Guangzhou Institute of Traditional Chinese Medicine and Materia MedicaDESIGN: A stratified randomized controlled animal trial.MATERIALS: Sixty-four Sprague-Dawley (SD) rats (Batch No. 2002A024), SPF grade, half male and half female,weighing 150 to 180 g, aged 6 to 8 weeks were purchased from Guangdong Medical Experimental Animal Center.Normal feed (total quantity of heat 6.9 kJ/g) was enriched with 23% protein, 53% carbohydrate and 5% fat. High fat emulsion (total quantity of heat 15.5 kJ/g) was enriched with 200 g/L lard, 200 g/L cholesterol, 10 g/L bile salt ox,200 g/L propylene glycol, 200 g/L tween-80. High fat and sugar feed (total quantity of heat 21.0 kJ/g) was enriched with 15% protein, 51% carbohydrate and 30% fat after adding 100 g/L glucose, 200 g/L lard and 100 g/L yolk powder then mixing and baking. Rosiglitazone was from GlaxoSmithKline Co Ltd. (Tianjin) (5 mg/tab, Batch No.02110012). Gliclazide was from Servier International and Tianjin Hua Jin Pharmaceutical Factory (100 mg/tab, Batch No.00232).METHODS: The experiment was carried out in Guangzhou University of Traditional Chinese Medicine from April to July in 2003. ① Sixty-four Sprague-Dawley rats, 16 of which were randomly sampled as the normal control group and had been fed with normal feed for 6 weeks. The others were modeled after medical literatures, each one was administered with high fat emulsion (10 mL/kg) by gavage once a day for 14 days. Rats whose FBG≥6.1 mmol/L or 2hBG≥7.8 mmol/L were selected, randomized into 3 groups according to body mass and blood glucose, i.e., negative control (model)group, rosiglitazone group and gliclazide group, there were 16 rats in each group. Except the normal control group, rats in the rosiglitazone group and gliclazide group were gavaged with rosiglitazone for 5 mg/kg and gliclazide for 100 mg/kg respectively, and those in the model group were gavaged with distilled water. All of the rats were fed with high-fat feed once a day for 28 days. From the 21st day, high fat emulsion was added once a day for 7 days. After fasting for 18 hours from the last administration, all the rats were recorded for FBG and administered dextrose 2.78 mol/10 mL .kg or dextrose and drug mixture 10 mL/kg by body mass. Two hours'later, 2hBG was recorded. ② Blood samples were collected from orbital plexus and serum was prepared for detecting the biochemical indexes and immunological indexes in serum, i.e., fasting serum glucose(FSG), total cholesterol (TC), triglyceride (TG), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), alanine aminotransferase (ALT), aspartate aminotransferase (AST),blood urea nitrogen (BUN), creatinine (Cr), tumor necrosis factor alpha (TNF-α) and fasting insulin (FINS). The insulin sensitivity index (ISI) was calculated: ISI=ln [1/ (FINS content×FBG content)]. After the rats were killed, their liver suspension was prepared for measuring the levels of TG, superoxide dismutase (SOD), glutathione (GSH) and malondialdehyde (MDA).MAIN OUTCOME MEASURES: ① FBG and 2hBG; ② FSG, blood lipids, TNF-α, FINS and ISI in serum; ③ TG, GSH, SOD and MDA in liver cells; ④ ALT, AST, BUN and Cr in serum. RESULTS: ① Results of FBG and 2hBG: The FBG and 2hBG in the rosiglitazone group [(3.2±0.3), (6.3±1.2) mmol/L]were lower than those in the modelcontrol group [(3.8±0.5), (8.1±2.1) mmol/L, P ＜ 0.01]. The FBG in the gliclazide group [(3.3±0.7) mmol/L] was lower than that in the model control group. ② Results of FSG, blood lipids, TNF-α, FINS and ISI: The FSG, TNF-α and FINS in the rosiglitazone group were (4.2±1.2) mmol/L, (246±45) μg/L and (133±45) pmol/L respectively, which were lower than those in the model control group [(6.6±1.5) mmol/L, (294±65) μg/L, (264±76) pmol/L,P ＜ 0.05-0.01], whereas ISI was higher than that in the model control group (-6.33±0.46, -7.46±0.95, P ＜ 0.01). The FSG and TNF-α in the gliclazide group [(4.1±1.1) mmol/L, (251±62) μg/L] were lower than those in the model control group (P ＜ 0.05-0.01). ③ Results of TG content, GSH deposit, SOD activity and MDA content in liver cells: The TG and MDA contents in liver cells in the rosiglitazone group [(1.00±0.38), (40±17) mmol/g] were lower than those in the model control group [(2.40±0.60), (171±63) mmol/g, P＜ 0.01], the GSH deposit and SOD activity [(51±14) mg/g, (583.45±50.01 ) nkat/g] were higher than those in the model control group [(2.40±0.60) mg/g, (450.09±66. 68) nkat/g, P ＜ 0.05-0.01].The TG and MDA contents in the gliclazide group [(1.20±0.38), (100±30) mmol/g] were lower than those in the model control group, whereas the GSH deposit [(46±15) mg/g] was higher than that in the model control group. ④ Results of ALT, AST, BUN and Cr in serum: The serum contents of BUN and Cr in the rosiglitazone group [(14.3±3.8) mmol/L,(33±9) μmol/L] were lower than those in the model control group [(19.2±5.6) mmol/L, (45±13) μmol/L, P ＜ 0.05].CONCLUSION: Both rosiglitazone and gliclazide can improve the insulin resistance induced by high fat feed.Rosiglitazone is superior to gliclazide in decreasing the high insulin level, decreaseing serum levels of BUN and Cr,improving reduced GSH deposit and enhancing SOD activity.

BACKGROUND: Xiaohuoluo pill can expel pathogenic wind, remove dampness and activate collaterals. It is used for treatment of Bi-syndrome due to wind-cold-dampness, pain and numbness in limbs.OBJECTIVE: To observe the pharmacological effect of Xiaohuoluo pills on secondary immune response, specific immunity (including cellular immunity and humoral immunity), non-specific immunity [including complement 3(C3), mononuclear phagocyte system (MPS) and red blood cell (RBC)adhesion function] and free radical injury as well as pain and many other inflammations in mice.DESIGN: A randomized controlled stratified trial.SETTING: Guangzhou Institute of Traditional Chinese Medicine and Chinese Materia Medica; Department of Pharmacy, Guangzhou Hospital of Traditional Chinese Medicine.MATERIALS: Totally 628 NIH and ICR mice of 6 to 8 weeks were involved in this trial. Xiaohuoluo pills (components: Dannanxing, Zhichuanwu, Zhicaowu, Dilong, Ruxiang and so on; Chenli Pharmaceutical Factory,Guangzhou; Brach No. 19980612) were used in this trial. Rabbit antimouse immunoglobulin G (IgG) and C3 antiserum reagent kit (Guangzhou Institute of Medicine and Health) and reagent kit for measuring the antioxidizing activity of superoxide dismutase (SOD) and the level of malondialdehyde (MDA) (Jiancheng Institute of Bioengineering, Nanjing) were used.METHODS: This trial was carried out in the Guangzhou Institute of Traditional Chinese Medicine and Chinese Materia Medica; Department of Pharmacy, Guangzhou Institute of Medicine and Health during September 1998 to December 1999. ① To observe the suppressive effect of Xiaohuoluo pills on cock red blood cell (CRBC)-induced secondary immune response: Eight-four ICR mice, male and female in half, were selected.Twenty of 84 mice served as blank controls; The other 64 mice were intraperitoneally injected with cyclophos-phamide (CY) of 0.2 g/kgonce. On the 4th and 12th days, CRBC was intraperitoneally injected into the mice twice to induce immunoenhancing pathological models to form secondary immune response. Mice served as blank controls were intraperitoneally injected with the same volume of normal saline; The immunoenhanced mice were assigned into 3 groups by a lot: CY group (n=20, CY, 40 mg/kg, intragastric administration, I.g.), Xiaohuoluo pills (n=21, Xiaohuoluo pills suspension, 5.54 g/kg, I.g.) and model group (n=20, distilled water, the same volume as other groups, I.g.); once a day within 7 successive days. 19 days later, the levels of serum IgG and C3 were measured with single immunodiffusion method, and the level of circulating immune compound (CIC) was measured with polyethylene glycol precipitation method. ② To observe the suppressive effect of Xiaohuoluo pills on delayed type hypersensitivity (DTH): Fifty-four ICR mice, male and female in half, were selected. On the 1st day, the mice were sensitized by subcutaneous injection of 10 g/L 2,4-dinitrofluorobenzen e (DNFB) of 50 μL for each. On the 4th day, the sensitized mice were assigned into 3 groups by a lot: Prednisone group (n=18, prednisone, 0.01 g/kg, I.g.), Xiaohuoluo pills (n=18, Xiaohuoluo pills suspension, 5.54 g/kg, I.g.), model group (n=18, distilled water, the same volume as other groups, I.g.), all once a day within 7 successive days. 11 days later, 10 g/L DNFB of 25μL was spread on the right ear of each mouse in each group. The swelling degree was calculated 24 hours later (The mass difference between right ear and left ear). ③ To observe the suppressive effect of Xiaohuoluo pills on immune adhesion function of RBC of mouse: Thirty-six NIH mice, male and female in half, were selected and assigned into 3 groups by a lot: CY group (n=12, CY, 20 mg/kg,I.g.), Xiaohuoluo pills (n=12, Xiaohuoluo pills suspension, 5.54 g/kg, I.g.)and blank control group (n=12, distilled water, the same volume as other groups, I.g.), once a day within 7 successive days. 7 days later, blood was taken from the orbit of mice for calculating the rosette rate of RBC-C3b receptor and the rosette rate of RBC immune compound. ④ To observe the suppressive effect o20 Mg/kg, I.g.),Xiaohuoluo pills group (Xiaohuoluo pills suspension, 5.54 g/kg, I.g.) , once a day within 7 successive days; IgM-type hemolytic concentration (HC50)was measured at 2 hours after the last administration on the 7th day [ (Sample absorption / Absorption at HC50 of CRBC) ×diluted time]. The levels of serum C3 and MDA and the activity of SOD were measured according to the method from corresponding reagent kit. ⑥ To observe the suppressive effect of Xiaohuoluo pills on agar granulation tissue hyperplasia in mice:Fifty-nine NIH mice were selected and given subcutaneous injection of 20 g/L agar of 0.5 mL for each. 24 hours later, the mice were assigned into 3 groups by a lot: diclofenac group (diclofenac, 10 mg/kg,I.g..), Xiaohuoluo pills group (Xiaohuoluo pills suspension, 5.54 g/kg, I.g.) and model group (distilled water, the same volume as other groups, I.g.), once a day within 7 successive days; On the 8th day, the mice were sacrificed. The hyperplasiainhibiting effect was presented in the form of the mass of agar granulation tissue in one kilogram body mass ⑦ To observe the suppressive effect of Xiaohuoluo pills on acetic distortion reaction: Sixty-three NIH mice were se lected and assigned into 3 groups by a lot: diclofenac group (diclofenac,50 mg/kg, I.g.), Xiaohuoluo pills group (Xiaohuoluo pills suspension, 5.54 g/kg,I.g.) and model group (distilled water, the same volume of other groups, I.g.),once a day within 2 successive days. At 2 hours after the last administration, the mice were given intraperitoneal injection of 0.1 mol/L acetic acid of 0.2 mL for each one. The times of distortion of mice within 20 minutes were counted. ⑧ To observe the effect of Xiaohuoluo pills on the acute exudative inflammation evoked by dimethylbenzene, croton oil and carrageenan, and the level of prostaglandin E in the inflammatory exudates:Totally 219 NIH mice were selected and assigned into 3 groups by a lot:diclofenac group (diclofenac, 50 mg/kg, I.g.), Xiaohuoluo pills group (Xiaohuoluo pills suspension, 5.54 g/kg, I.g.) and model group (distilled water, the same volume of other groups, I.g.) once a day within 2 successive days. At 2 hours after the last administration, dimethylbenzene of 25 μL was spread on the right ear for 20 minutes, or croton oil of 25 μL was also spread on the right ear, 4 hours later, the swelling of right ear was calculated (mass of right ear-mass of left ear). 10 g/L carrageenan of 20 μL was subcutaneously injected into the right foot, 3 hours later, the swelling degree was calculated (The difference of right foot and left foot); and the level of prostaglandin E in the inflammatory exudates was measured. ⑨ t test(t' test for heteroscedasticity) was used for comparing the difference in measurement data among groups.MAIN OUTCOME MEASURES: Pharmacological effect of Xiaohuoluo pills on secondary immune response, specific immunity, non-specific immunity and free radical injury as well as pain and many other inflammations in mice.RESULTS: Totally 628 NIH and ICR mice were involved in result analysis. ① The level of IgG and CIC of mice in the model group was significantly higher than that in the other 3 groups respectively (P ＜ 0.01),while the level of C3 was significantly lower than that in the other 3 groups (P ＜ 0.05 to 0.01). ② The swelling degree of mice in the diclofenac group and Xiaohuoluo pills group was significantly lower than that in the blank control group respectively ( both P ＜ 0.01). ③ The rosette rate of RBC-C3b receptor and RBC immune compound in the blank control group was significantly higher than that in the other 2 gro ups respectively (P ＜ 0.01). ④ The phagocytic index (K value )in the diclofenac group and Xiaohuoluo pills group was significantly lower than that in the blank control group, respectively (both P ＜ 0.01).⑤ IgM-type HC50 and the level of serum MDA of CY group and Xiaohuoluo pills group were obviously lower than those in the immune control group (P ＜ 0.01),while the level of C3 was higher than that of immune control group, there was no significant difference in the activity of serum SOD between CY group or Xiaohuoluo pills group and immune control group (P ＞ 0.05). ⑥The ratio of agar granulation tissue mass to body mass in the diclofenac group or Xiaohuoluo pills group was significantly lower than that in the model group(P ＜ 0.01).⑦ The times of distortion of mice within 20 minutes in the diclofenac group or Xiaohuoluo pills group were signifi cantly less than those of model group(P ＜ 0.01,0.05).⑧The ear swelling degree of dimethylbenzene-induced inflammatory models and croton oil-induced inflammatory models,and foot swelling degree of carrageenan-induced acute inflammatory models as well as the level of prostaglandin E in the inflammatory exudates in the diclofenac group were significantly milder or lower than those in the model group(P ＜ 0.05 to 0.01),and the level of prostaglandin E in the inflammatory exudates in the Xiaohuoluo pills group was significantly lower than that in the model group (P ＜ 0.01).CONCLUSION: Xiaohuoluo pills possess pharmacological effects of immunosuppression, anti-proliferative inflammation, analgesia and antioxidation.

AIM: To predict MHC class Ⅰ binding peptides by using neural network ensembles. METHODS: As a combination of neural networks, neural network ensemble (NNE) was here used to improve the predictive performance. Based on a database of 628 nonamers and their classified binding capacities, the generalized NNEs were used to classify peptides respectively with non, low, moderate and high binding capacities to MHC class I molecule encoded by gene HLA-A*0201. The predictive power of NNE was further evaluated by running generalized NNE on a set of actual T-cell epitopes. RESULTS: The generalized NNEs achieved an average predictive hit rate of 0.8 for the above classifications. In addition, NNE was also efficient in the prediction of the potential T-cell epitopes, and about 84% of the actual T-cell epitopes were among the potentially antigenic peptides with high and moderate affinities. CONCLUSION: The NNEs can be applied in the prediction of MHC class Ⅰ binding peptides, and moreover, after proper modifications, they can be conveniently extended to cover peptides with any length and thus suitable for the prediction of peptides binding to other MHC class Ⅰ or even class Ⅱ molecules.

BACKGROUND: Silibinin has broad pharmaceutical effects, such as anti-free radicals, anti-lipid peroxidation, anti-lipoid oxidase, anti-glutathione (GSH) depletion, anti-neoplastic and serum lipid-lowering effects. Clinically, silibinin is often used in treating alcoholic liver disease. OBJECTIVE: To investigate the pharmacological mechanism of silibinin for alcoholic fatty liver in rats. DESIGN: Randomized and controlled study.SETTING: Guangzhou Hospital of Traditional Chinese Medicine.MATERIALS: The experiment was conducted at the Animal Experimental Laboratory of Guangdong Pharmaceutical Institute from August to October 2003. Totally 57 SD rats, without unusual bacteria, weighting (150±10)g and of either gender, were selected. Yiganling tablets containing 38.5 mg silibinin were produced by Zhuzhou No.3 Pharmaceutical Factory (Batch No. 20020808).METHODS: Among the 57 SD rats, 18 rats were regarded as normal control group. Rats in normal control group were administered with normal saline by gavage, and fed with normal food and distilled water in place of alcohol for 10 weeks. Rats in model group and silibinin group were fed with high-calorie food and 100 mL/L alcohol for 6 weeks to establish model of rat alcoholic fatty liver. The other rats were divided into model control group (n=18) and silibinin group (n=21). Rats in model control group were treated with distilled water while those in silibinin group were treated with 100 mg/kg silibinin. Meanwhile, 100 mL/L ethanol and hyperalimentation feed were given for 4 weeks. After animals were killed, TG, SOD, GSH and MDA levels were measured with liver suspension.MAIN OUTCOME MEASURES: Contents of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (AKP), total cholesterol (TC), triacylglycerol (TG), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), tumor necrosis factor (TNF)-α , and transforming growth factor (TGF)-β1.RESULTS: All the 57 rats entered the final analysis. Silibinin could inhibit the activities of serum AST, ALT and AKP [(2 550.5±400.1), (533.4±100.0), (2 217.1±750.2)nkat/L], and the differences were significant as compared with those in model control group [(3 600.7±666.8), (800.2±100.0), (2 900.6±1 333.6) nkat/L, P ＜ 0.05-0.01]. Contents of TG, LDL-C, TNF-α and TGF-β1 in silibinin group [(1.8±0.8), (0.17±0.04), (6.66±1.38), (24.1±4.1) mmol/L] were lower than those in model group [(2.8±1.4), (0.20±0.05), (7.81±1.06), (28.8±6.3) mmol/L] with significant differences (P ＜ 0.05-0.01). Silibinin could increase the content of HDL-C but decrease the contents of TG and MDA (P ＜ 0.05-0.01), and improve SOD activity as well as hepatocyte and fatty degeneration (P ＜ 0.01).However, it had no obvious effect on the content of reduced estathion (P ＞ 0.05).CONCLUSION: Silibinin can inhibitthe formation of alcoholic fatty liver in rats. The pharmacological mechanism of silibinin may involve anti-oxidation, removing free radicals, inhibiting lipid peroxidation, regulating blood lipid component, reducing fatty sediment in liver, and anti-immunoinflammation and anti-hyperplasia effects.